The invention relates to an electro-optical scanning device comprising a mounting section, which is normally moved only to access different recording tracks and is hereinafter referred to as a stationary section, a section which is movable relative to said stationary section and which comprises a lens having an optical axis, and supporting means disposed between the stationary section and the movable section for movably supporting the movable section, which movable section is movable at least substantially along a first axis parallel to the optical axis, in order to form at least one radiation spot on a surface to be scanned, and at least substantially along a second axis oriented transversely of the optical axis, in order to follow a recording track in said surface, there being provided an electromagnetic actuator comprising first actuator means provided on the stationary section and second actuator means provided on the movable section, which actuator means cooperate magnetically with one another via an air gap in order to drive the movable section.
Such a scanning device is known from WO 91/01549 (herewith incorporated by reference). The known electro-optical scanning device has an objective lens for optically scanning a surface provided with information tracks. The objective lens, which has an optical axis, is mounted in a movably supported holder. The holder with the objective lens is movable parallel to the optical axis and parallel to the surface to be scanned. For this purpose the holder is pivotally connected to a support by means of two holding devices. The holding devices, which are wholly made of a plastics, each have two end pasts, two intermediate parts and two central parts, which pans are interconnected by plastics integral hinges. It is generally known that plastics exhibit a creep effect in the course of time, particularly at higher temperatures. In the known scanning device, in which the supporting device for the objective is wholly made of a plastics, the creep effect leads to deformations of the integral hinges and, consequently, to deviations of the position and the orientation of the objective lens relative to the originally established references.
An accurate support is of great importance in order to maintain the position in the tracking direction and the orientation of the lens relative to the information tracks during scanning because current scanning systems do not have a reference for this, so that no corrections can be made. Deviations of the position of the lens in the focusing direction can generally be corrected because most scanning systems use the position of the surface to be scanned as a reference for the focusing position of the objective lens, but such corrections lead to an increased power consumption. Particularly in battery-powered apparatuses, especially portable apparatuses, an unnecessary power consumption may be very undesirable.